Electro-magnetic actuating means



Jan. 23, 1962 P. c. PlNToN 3,018,035

ELECTRO-MAGNETIC ACTUATING MEANS Filed Sept. 27, 195? 5 Sheets-$heet 1 Jan. 23, 1962 P. c. PlNToN 3,018,035

ELECTRO-MAGNETIC ACTUATING MEANS Filed Sept. 27, 1957 5 Sheets-Sheet 2 83 Fl'g. 6

Jan. 23, 1962 P. c. PINToN 3,018,035

ELECTRO-MAGNETIC ACTUATING MEANS Filed Sept. 27, 1957 5 Sheets-Sheet 3 states liatcnt @thee dldd Patented dan. 23, i952 3,018,035 ELECTRU-MAGNETEC ACTUATNG MEAN Pierre (I. Pinton, Paris, France, assignor to Compagnie des Machines Bull (Societe Anonyme), Paris, France Filed Sept. 27, 1957, Ser. No. 686,711 Claims priority, application France Oct. 5, 1956 2 Claims. (Cl. 234-108) The present invention relates to improvements in devices for the operation of mechanisms by means of electromagnets.

lt is known that the attractive force exerted on the movable armature of an electromagnet having a variable air gap, when the latter is energised, may approximately be regarded as inversely proportional to the square of the air gap, that is to say, that this force increases very rapidly when the air gap is reduced. There are applications in which it would be desirable for the maximum effort to be utilisable as soon as the electromagent is energised and that a smaller force should thereafter be available,

Electro-magnet constructions are known which satisfy this latter condition (electro-magnet having a plunger core without a yoke or electro-magnet having a constant air gap) but these constructions, which have not a good output as defined by the electric current consumed in relation to the force supplied, also have greater overall dimensions than electro-magnets having a variable air gap with equal power.

One object of the invention is to provide an arrangement permitting a better utilisation of the variable force supplied by the moving armature of an electro-magnet having a Variable air gap as a function of the variation of its air gap during its closing.

The arrangement according to the invention is more particularly applicable to punching mechanisms actuated by electromagnets for punching perforations in sheets or tapes of resistant material such as paper, board, plastic material or metal.

The arrangement according to the invention permits a better utilisation of the force supplied by the armature of an electromagnet, and a considerable reduction of the power of the electro-magnet required for a given operation.

Another advantage of the invention is that, owing to the reduction which it permits in the power of the electromagnet required for a given operation, the construction can be made more compact and the mechanism simplitied.

ln an arrangement designed in accordance with the invention, the force supplied by the closing of the armature of an electro-magnet, when the latter is energised, iS transmitted to the utilisation member through a resilient member so designed that, when a suiiicient resistance is set up to the movement of the utilisation member, at the eginning of the travel of the moving armature of the electro-magnet, the energy supplied by the latterY is stored at least partly by compression or extension of the resilient member and that, at or near to the end of the movement of the moving armature of the electro-magnet, the resistance set up to the movement of the utilisation member is lower than the compression or extension force of the resilient member, the latter expands and transfers to the utilisation member the energy stored at the beginning of the travel of the moving armature of the electro-magnet.

Further advantages and features of the invention will ecome apparent in the course of the following description and with `reference -to the accompanying drawings, in which:

FlGURE i is a diagrammatic view showing partly in section the members controlling a punch in a punching machine of known type for record cards or tapes which is electrically controlled and not provid-ed with the irnprovements according to the invention,

FGURE 2 is a diagrammatic sectional view of a punching mechanism provided with an arrangement designed in accordance with the invention,

FGURE 3 is a graph showing approximately in dashdotted lines for a known device and in solid lines for a device according to the invention, the variations of the force which can be developed by the moving armature of an electro-magnet as a function of the variations of its air gap when it is energised, on the one hand, and variations of the force transmitted by the said electro-magnet to a punching `device in `a punching operation, on the other hand,

FlGURE 4 is a graph indicating the relative movements of the armature of the electro-magnet and of the punch in an arrangement designed in accordance with the invention,

FlGURE 5 is a diagrammatic sectional view of a mechanism for punching record cards or tapes, provided with an arrangement designed in accordance with the invention,

FIGURE 6 is a View along the line 6 6 of a part of FIGURE 5, showing a `detail of the construction of the resilient member of the mechanism,

FGURE 7 shows another constructional form of a punching mechanism according to the invention, and

FIGURE 8 is a sectional View along the line S-S of FIGURE 7, showing the details of the construction of the resilient member of the mechanism.

A record card l@ (FGURE l) is positioned in a punching device comprising a row of punches, of which only one punch il is visible in the sectional view, the others being concealed by the punch shown. The punch lll is normally pushed downward by a spring l2 compressed between a collar lia fast with the punch, on the one hand, and by a fixed bar lic, on the other hand, in which are formed the apertures for guiding the punches. The collar lla of the punch rests on another bar for guiding the punches lib, lwhich is fixed and fast with the frame of the machine. When the punch is pushed upwards by an actuating mechanism which will hereinafter be described, the collar lla of the punch compresses the spring i2 and the punch il penetrates into a cutting die i3 formed in a die bar i3d. When a card lli is engaged between the punch and the die, it is perforated and the paper cut out from the card is pushed by the punch through the die and collected in a trough i4, whence it is discharged by an appropriate device (not shown). The force exerted on the punch for eiiecting the punching of the perforation is supplied by the energisation of an electro-magnet l5 which attracts a movable blade 16 fast with a punching bar i7. The punching bar i7 can act on the punch only through a member l called the interposed member which under the action of the movable blade Ztl of an electro-magnet i9 is disposed between the head lid of the punch ll and the punching bar 17. A seri of interposed members i8 is provided, one for each punch of the row of punches, each interposed member being controlled by a corresponding electro-magnet i9. For controlling the punching of a plurality of perforations in a column, the interposed members of a number of punches may be simultaneously actuated. A return spring 2l returns the interposed member i8 against the abutment 22 when, after the punching operation, the electro-magnet 19 is no longer energised. The basic arrangement hereinbefore described is very widely used in machines employed for the perforation of record cards or tapes. lts main advantage is that it permits the control of the interposed members of the punches with relatively weak currents, but the current necessary for the energisation of the electro-magnet l5 which supplies the punching work is much greater. The dimensions of the electro-magnet 15' are also much larger than those of the electro-magnets 19, which only control [he interposed members. A disadvantage of this arrangement resides in that the positioning of the interposed embers introduces a dead time into the succession of the elemental operations of which the cycle of a punching operation is composed. This is a very important disadvantage in the case of high-speed punching machines which are employed Imore particularly for punching tapes. Rapid machines for punching tapes have already been proposed, in which the perforations are made by lowering a punch fixed to the end of the armature of an electromagnet suciently powerful to perforate parchment paper without hesitation. This arrangement necessitates the transmission of a considerable electric current for the control of each electro-magnet which must supply the necessary force for the punching, and this arrangement Y has therefore often been abandoned in favour of the arrangement comprising interposed members which is, however, less rapid in principle. In order more clearly to set forth the advantages of the invention, which will hereinafter be shown in detail, over the arrangements mentioned in the foregoing, reference will be made to the graph of FlGURE 3, which shows in dash-dotted lines the method of operation of a punching electromagnet operating with or without interposed members. The variations of the air gap of the electro-magnet are plotted along the abscissae and the reference 2 corresponds to the maximum air gap for which the force developed by the electro-magnet is minimum, when the latter is energised, and the reference o corresponds to the minimum air gap for which the force developed by the electro-magnet is maximum. The forces are plotted along the ordinates and the curve 30 represents approximately the variation of the force available on the moving armature of the electro-magnet as a function of the variation of the air gap when the coil of the electromagnet is energised with a direct current of substantially nstant voltage. The curve 31 in the same gure represents the variations of the force transmitted to the punch by the electro-magnet during the punching. For the eX- planation, reference `will be made to the drawing of FIG- URE l, but in order to simplify the reasoning the interposed member 18 will be disregarded and it will be assumed that the head of the punch 11 has the form represented by the line 11e and is extended into the immediate vicinity of the punching bar 17 in the inoperative position. Under these conditions, when the electro-magnet 15 is energised, the blade 16 is attracted and the punching bar 17 is brought into contact with the head of the punch 11 and lifts the latter. The electro-magnet must then supply the force necessary for compressing the spring 12. This force, at the beginning is represented by the point 32 along the ordinates in the graph of FIG- URE 3. The punch is then brought into contact with the card 10, which is urged against the die 13 and sets up a considerable resistance to the passage of the punch. The forces supplied by the electro-magnet increases rapidly, as indicated by the line between the points 33 and 34 of curve 31 of the graph. At a given instant, the punch passes through the card and cuts out a perforation therein, while the force exerted by the electro-magnet remains substantially unchanged as indicated by the points `311i and 3S of the curve. When the punch has passed through the card, the force supplied by the electro-magnet decreases very rapidly as indicated by the curve from the point 35 to the point 36. At this instant, the electromagnet only supplies the force necessary for compressing the spring 12 and forcing the cut-out paper through the die as indicated by the curve from the point 36 to the point 37. When the electro-magnet is de-energised, the spring 12 returns the punch to its bottom inoperative position and also returns the punching bar 17 against the abutment 23, against which it is maintained by a return al spring 24, the function of which has been neglected in the foregoing explanation.

ln order that the punch may perforate the card safely, it is obvious that the curve which represents the force available on the moving armature of the electro-magnet must pass at 3S (FlGURE 3) very much above the point 3d 35 of the curve 3i. The point 35 determines what power the electro-magnet requires. it is sometimes permissible for this curve to pass very close to and even below the part 34-35 of the curve, the recovery, at the moment of the maximum effort, of the kinetic energy stored by the moving members in the mechanism being relied upon. A mechanism designed on these bases has insuficient operating reliability.

The discharge through the die of the paper cut out from the card by the punch is of Very great importance because in the case where the paper cut out is not pushed far enough into the die it may return with the punch and take up a position across a perforation in the card, in which it may form a projection and prevent the movement of the card past the punches for the positioning of another record column. ln some cases, the card thus wedged cannot be extracted from the machine without being torn. This difculty is particularly to be feared in so-called visible card punching machines, in which the punching is effected from below in order that the cards may not be concealed from the eyes of the operator except in the part where it is covered by the row of dies. in this arrangement, which is illustrated in FIGURES l, 5 and 7, the paper cut and detached from the card is likely not only to be returned into the plane of the card by the punch, but also to fall back therein under the action of its own weight, that is to say, itis important that the paper cut out should be pushed far forwards and forced out of the die by the punch. ln the following, it will be seen that the arrangements according to the invention ensure on the one hand a better utilisation of the force supplied by the punching electro-magnet but also ensure on the other hand a better ejection of the cut-out paper through the die.

The drawing of FIGURE 2 illustrates diagrammatically in section a punching mechanism actuated by an electromagnet and provided with an arrangement designed in accordance with the invention. The moving armature it? of an electro-magnet 41 is connected to a perforating punch i2 through a rod 4S and a resilient member comprising a spring 43 which is compressed between a collar 435 fast with the punch and the end 47 of a hollow cylinder 44. When the spring is further compressed within the hollow cylinder the abutment 16 of the punch bears against the end 47 of the hollow cylinder and limits the compression of the spring. A spring e9 around the punch 42 bears on the one hand against the fixed plate 52 and on the other hand urges the assembly comprising the punch, the resilient member, the rod 43 and the moving armature 46 of the electro-magnet against an abutment 5i). The spring 419 is constructed to ilex more rapidly than the spring 43 and the compressed spring 43 is not strong enough to cause the punch i2 to penetrate into the card 51. The operation of the device illustrated in FIGURE 2 will be described with reference to the graphs of FIGURE 3.

When the electro-magnet 41 is energised, the armature dit exerts a force sufficient to urge the punch i2 against the card 51 while compressing the spring 49 between the guide plate 52 and the face 53 of the hollow cylinder d4. This force increases slightly during the compression of the spring 49 as shown in the graph by the line from the point 32 to the point 33 (FIGURE 3). Then, when the compression of the spring i3 commences, the force supplied by the electro-magnet increases as shown by the line from 33 to 61 in the graph. Then comes the force for compressing the spring 43, which is indicated by the line 61 to d2 in the graph. When the abutment d6 of the punch encounters the end 47 of the hollow cylinder containing the spring, the force of the electro-magnet increases as indicated by the line 622-63 of the graph. At this instant, the

force exerted by the armature 4i? of the electro-magnet is transmitted directly to the punch, which perforates the card. At a given instant, indicated by the point 63 in the graph, the card suddenly yields, a piece of cut-out paper is detached from the card and the resistance set up to the advance of the punch by the card decreases rapidly as indicated by the line 6l) in the graph. The spring 43 expands, point 64 to point 65 of the graph, and rapidly forces the cut-out paper through the die 54. After expansion of the spring 43, the punch advances again, point 65 to point 37 in the graph, under the action of the moving armature of the electro-magnet. The spring 49 which has been compressed by the movement of the moving armature of the electro-magnet during the punching expands when the latter is de-energised and returns the moving armature against the abutment 59.

The graph of FIGURE 3 shows that, by reason of the provision of a resilient member in the mechanism according to the invention, the peak of the eifort supplied by the moving armature of the electro-magnet for punching the card has been shifted from the point 35 to the point 63. Consequently, the force developed by the electro-magnet necessary for actuating a punching mechanism under the same conditions of reliability of operation passes from the curve 3d to the curve 66, which is that of a much less strong electro-magnet, that is to say, that of an electromagnet having smaller overall dimensions and necessitating a weaker electric current for its actuation. It will be seen from the approximate curves shown by way of example in FIGURE 3, that for example, at the point 1, that is to say, at the midpoint of the travel of the armature, the force supplied by an electro-magnet conforming to the characteristics indicated by the curve 66 corresponds substantially to one half of the force supplied by an electromagnet conforming to the characteristics indicated by the curve 30.

r[he graph of FIGURE 4 shows the relative movements of the moving armature of the electro-magnet and of the punch. The movements of the moving armature are plotted (on the same scale as in FIGURE 3) along the abscissae and the movements of the punch are plotted along the ordinates, also on the same scale. The line from the point 79 to the point 71 of the curve (FIGURE 4) indicates that the punch advances with the moving armature. The line from the point 71 to the point 72 indicates that the punch is stopped by the card while the spring 43 (FIGURE 2) is compressed by the movement of the moving armature. The point 72 indicates the instant when the abutment 46 cornes into contact with the end 47 of the cylinder 44 containing the spring 43. The line from 72 to 73 shows the movement of the moving armature when it is pushing the punch through the card. In the graph of FIGURE 4, the section 72-73 is relatively extended by reason of the fact that a bevelled punch is provided as indicated in FIGURE 2. The point 73 of the curve shows the instant when the cut-out paper is detached and the line 73-74 represents the movement of the punch while the spring 43 is expanding and the cut-out paper is being forced through the die. The line from the point 74 to the point 75 shows that the moving armature of the electro-magnet and the punch terminate their movement at the same speed. When the energisation of the electro-magnet is interrupted, the moving armature and the punch are brought together, by a movement represented by the straight line 78 from 75 to 7i), to the inoperative position under the action of the spring 49 (FIGURE 2) which expands.

The simultaneous movement of the moving armature and of the punch as indicated by the line from the point 74 to the point 75 of the graph of FIGURE 4 may appear to be superfluous, and it would in fact be suicient within the spirit of the invention for the armature of the electro-magnet to cease advancing as soon as the punch has passed through the card and to cause the spring 43 to force the cut-out paper through the die in expanding,

that is to say, to stop the movement of the armature at the vertical I3-76 of the graph. The arrangement described has been designed for considerations of reliability of operation. In fact, even in the event of breakage of the spring 43, the device could continue to operate. However, under less secure conditions from the viewpoint of the discharge of the cut-out pieces of paper, the punch would continue to force the cut-out paper through the die as indicated by the line from point 73 to point '77 (FIGURE 4) after perforation of the card.

he resilient member may be designed in any manner considered appropriate without departing from the spirit of the invention. For example, the abutment 46 (FIG- URE 2) may -be omitted if a spring 43 is provided which, after a predetermined compression, has its convolutions contiguous so as to transmit directly to the punch the force developed by the moving armature of the electromagnet. In the same order of ideas, the spring 43 may be of any appropriate form and may, for example, be made suiciently strong to permit a variable compression as a function of the resistance offered by the sheet to be perforated and to expand as soon as this resistance has been overcome by perforation.

In the arrangement illustrated in FIGURE 2, the resilient member comprises a spring working in compression. In the following FIGURES 5 to 8, the resilient members work in tension.

FIGURE 5 shows a punch titl provided with a collar 81 which rests on a tixed guide plate 32. A return spring 83 is compressed between the collar SI of the punch and a fixed upper guide bar 34. A lever 86 adapted to pivot about a pin 87 bears at one end on the head 85 of the punch. Two links 83a (FIGURE 6) and Sb are mounted on the lever 36 pivotable about a pin 89. The links 38a and 83h have formed in their lower ends slots 93 and 94, through which there is passed a pin 90 fast with the moving armature 9i of the electro-magnet 92, which is of the plunger core type. A spring operating in tension is engaged at one end on the lever 86 and at the other end on the moving armature 91 and tends to bring the members S6 and 9i together by applying the pin 99 against the upper edge of the slots 93 and 94. The operation of the arrangement of FIGURE 5 is similar to the operation of the arrangement of FIGURE 2, which has been described.

When the electro-magnet 92 is energised, the moving armature 91 is urged downwards. A movement is transmitted through the spring 95, which is in tension, and through the lever 86 to the punch du, which compresses the spring by means of its collar 81 and bears against the card 96 to be perforated. Due to the resistance offered by the card to the passage of the punch, the spring 95 is extended by the electro-magnet until the pin 99 bears against the lower edge of the slots 93 and 94. From this instant, the force developed by the electromagnet is transmitted by the links 33a and f8b and by the lever 86, directly to the punch, which perforates the card. The portion cut out of the card yields, the spring 95 can contract and the punch 80, which advances rapidly, forces the cut-out paper through the die 97 into the trough 98, from which it is removed by a known discharge member 99. The said member may be, for example, similar to the member 380 illustrated in FIG- URE 8 of French Patent No. 714,813, tiled on April 4, 1931 and published on November 20, 1931. When the electro-magnet 92 is no longer energised, the spring 33 expands and withdraws the punch Si) from the die and brings the moving armature 91 of the electromagnet to its inoperative position. The devices for actuating the punches of a row of punches in a punching machine may be disposed alternately on either side of a plane exten-ding through the axis X-Y of the punches in order to provide the maximum space for the provision of the electro-magnets.

In the arrangement illustrated in FIGURES 7 and 8,

the spring of the resilient member also works in tension, but the mechanical parts of the resilient member are pivotally mounted. One end of a Spring 180 is engaged in a groove 101 formed in a member 1.02 acting as a lever. The other end of the spring 100 is engaged in a groove 103 formed in a member 104, 'which is pivotally mounted on a pin 105, on which the lever 102 also pivots. A pin 106 fast with a member 104 is urged under the action of a spring 108 against the upper edge of a hole 107 formed in the member 102, whereby the movement of the grooves 181 and 103 towards one another under the action of the spring 100 is limited. The member 104 is connected to the moving armature 108 of an electro-magnet 127 by means of a link 109 pivotally connected at its ends to pins 110 and 111.

When the electro-magnet 127 is energised, the punch 112 bears against the card 113 to be perforated, the lever 102 is held fast and the member 104 continues to pivot about the pin 105. The pin 106 leaves the upper edge of the hole 107 while the spring 100 is extended by the movement of the member 104 in which it is engaged by means of the groove 103. A flange 114 on the member 104 is brought into contact with the upper part 115 of the member 102 and limits the extension ci the spring 100. The force developed by the electro-magnet 127 is then transmitted directly to the punch 112 for the perforation. The perforation of the card permits the expanding of the spring 100, which advances the punch 112 rapidly into the cutting die 117. When the electro-magnet 127 is thereafter de-energised, the spring 116 returns the punch 112 and the moving armature 108 of the electro-magnet to the inoperative position. The arrangements illustrated in FIGURES to 8 show diagrammatically mechanisms of compact construction which are capable of operating at very high perforating speeds, under remarkable conditions of operating reliability with electric control currents of relatively low power. The arrangements described by way of example are in no way limitative and any modiiications in form and in detail and any adaptations may be applied in accordance with circumstances and with the applications without departing from the scope of the invention.

I claim:

1. Mechanism for punching record cards or tapes comprising an electro-magnet having an armature, a hollow member xed with said armature, said member being opened in its upper part, a punching organ comprising a punch adapted to slide in said hollow member, an inside abutment in said hollow member adapted to lean against its upper surface, and a stop member located inside said hoilow member thus limiting the displacement of said hollow member in relation to the punch, a rst spring of slight resistance, concentric to said punch and connected at one end to a fixed organ near the cutting end of said punch, and at the other end to said punching organ, a second spring of stronger resistance connected at one end to said punching organ, and at the other end to the interior face of said hollow member.

2. Mechanism for punching record cards or bands, comprising an electro-magnet having an armature, a hollow cylinder connected to said armature by a rod, and having an aperture at its upper part, a punching organ comprising a punch adapted to slide in said hollow member, an inside ring fixed with said punching organ, located inside said hollow member and adapted to lean against the upper face of said hollow'member, and a stop member located in the extension of the punch inside the hollow cylinder, the free extremity of which is next to the inferior face of said cylinder, a rst spring of slight resistance, concentric to said punch, connected at one end to a fixed member guiding the cutting edge of said punch, and at the other end at the upper face of said hollow cylinder, a second spring stronger than the rst, concentric to said stop part, connected at one end to said ring, and at the other end to the inferior surface of said hollow member.

References Cited in the file of this patent UNITED STATES PATENTS 352,600 Wright Nov. 16, 1886 1,605,644 Carnahan Nov. 2, 1926 2,519,477 Kind Aug. 22, 1950 2,664,815 Schuessler Jan. 5, 1954 2,704,125 Taylor Mar. 15, 1955 2,798,548 Leirer July 9, 1957 2,800,178 Taylor July 23, 1957 2,881,833 Hoffee Apr. 14, 1959 2,901,237 Gruer Aug. 25, 1959 

